1. Field of the Invention
This invention is in the field of calculators which accept a number of parameters, and compare the parameters in a given manner to obtain a given result. More particularly, this invention pertains to a hand calculator having manually rotatable discs, each of which carries a plurality of scales and indices which are selectively registrable.
2. Brief Statement of the Prior Art
Numerous calculators are available in the art which are operable by selective manual registration of relatively slidable or rotatable scales and indices. These vary all the way from the simple general function multiplication slide rule to rather complex multiple scale calulators. Further, special purpose calculators have been provided to determine the relative economy between appliances using gas and eletricity; the radiating area required for various heating systems; and humidity calculations relative to certain air conditioning factors. However, no known calculator is available for determining the advisability of paying a higher price for a higher efficiency product such as an air conditioner given a wide variety of variables to be considered in the calculation.